Mineral Oil Findings in Recycled Fibre Food Packaging
Recycled paperboard packaging requires verified functional barriers and HPLC-GC-FID test dossiers to prevent gas-phase MOSH and MOAH food contamination.
PVOH Barrier
Oxygen Resistance
Water soluble polymers provide an exceptional defense against the passage of gases when applied as a coating to paper substrates. A pvoh barrier is created by applying polyvinyl alcohol in a thin layer, which forms a dense crystalline structure upon drying. This material is particularly effective at blocking oxygen, nitrogen and carbon dioxide, making it ideal for food packaging that requires a modified atmosphere.
It also acts as a powerful shield against the migration of mineral oils from recycled board.
Humidity Sensitivity
Performance of this coating drops significantly when it is exposed to high levels of moisture. Because a pvoh barrier is hydrophilic, the polymer chains swell and the gas resistance decreases as the relative humidity rises. Manufacturers often overcome this by blending the material with cross linking agents or by covering it with a protective layer of water resistant lacquer.
This ensures the barrier remains functional even in damp storage environments.
Sustainable Application
Biodegradability and repulpability are the key environmental benefits of using this chemistry in packaging design. A pvoh barrier can be easily washed off during the recycling process, allowing the underlying paper fibres to be recovered without contamination from plastic films. This makes it a preferred choice for companies looking to replace traditional laminates with more circular alternatives.